Measurement of social support across women from four ethnic groups: evidence of factorial invariance.

To examine whether a multidimensional social support instrument can be used for comparative research in four diverse ethnic groups of women (African American, Latina, Chinese, non-Latina White). The social support instrument was administered as part of a larger survey to 1,137 women. We tested the reliability and validity of this instrument. A confirmatory factor analytic (CFA) framework was used to test for the invariance of the instrument's psychometric properties across ethnic groups. We used multitrait scaling to eliminate items that did not meet the item-convergence criterion (r > 0.30) and where items were non-convergent items in at least three groups. A series of nested CFA models assessed the level of factorial invariance. One thousand seventy-four women completed the survey; Their mean age was 61 years with Chinese and Latinas reporting lower education compared to non-Latino Whites (p <. 001). A four-factor model (Tangible, Informational, Financial, Emotional/Companionship) fit within each ethnic group separately, suggested good fit. Multi-group CFA supported configural and metric invariance across all ethnic groups. Only partial scalar invariance was supported. This 8-item instrument is a reliable and valid tool that can be used as a multidimensional measure of social support. It can used to examine social support within one ethnic group and for comparative research across diverse ethnic groups of women.